Spin-on type filters

ABSTRACT

A replaceable filter which includes an outer perforated canister and an inner star-shaped, perforated canister around which is woven a plurality of layers of nonwoven relatively open-pored filter material. A relief valve surrounds the inner stem in the form of a resilient washer which lets oil bypass the filter without dumping dirt or oil back into the oil stream.

United States Patent 1 3,625,363

[72] Inventor John Eberle 5 R fere e Cited (Zjgigjfth Ave. S.W.,Calgary, Alberta, UNITED STATES PATENTS [2|] Appl. No. 14,486 3,085,6884/1963 Eberle 210/232 b 1,165,640 Utzetal. [45] Patented 7,19713,256,989 6/l966 Hultgren 2 lO/l 30 [32] Priority Feb. 27, i969 PrimaryExaminer-Frank A. Spear, Jr. [33] Japan Atlorney- Kent & Ade [3 l] 44/14967 ABSTRACT: A replaceable filter which includes an outer per [54]SPIN-0N TYPE FILTERS forated canister and an inner star-shaped,perforated canister ll Claims, 4 Drawing Figs. around which is woven aplurality of layers of nonwoven rela- 52 us. Cl 210/130 open'pmed Asummds inner stem in the form of a resilient washer which lets oil2l0/l34,2lO/I36,2l044l,2l0 9 l4 210/494 bypass the filter withoutdumping dirt or oil back into the oil 51] lnt.Cl ..B01d35/l4,

B0ld27/l0 Stream- 50 FieldofSearch 210/130,

134,136, 441, 442, 443, 494, DIG. l7

l4 ll 000 0 0 L 40 000 0 o z Z I I7 0000 0 7W Z B 2 AMA SPIN -N TYPEFILTERS This invention relates to new and useful improvements inspin-on-type filters for oil systems of automotive or truck engines andthe like.

conventionally, this type of filter is screw threadably engageable overan oil conduit and, when replaced, is removed and disposed of. Thisconventional type of filter suffers from several disadvantages.

Firstly, it is difficult to engage the filter casing with a wrench orthe like due to the lack of space where such filters are usuallyinstalled.

Secondly, it is relatively expensive to replace an entire filter andelement thus adding to the cost of maintenance.

Thirdly, all such filters include a bypass valve which enables oil tobypass the filter and pass directly to the bearings in case the filterelement is clogged or when the oil is cold and relatively thick.Conventional filterswith such bypass valves, are constructed so that theoil bypassing the filter picks up dirt upon the filtering media anddumps same into the main engine oil supply thus destroying theusefulness and effect of the filter element.

The present invention overcomes all of these disadvantages as willhereinafter be described and in particular provides a filter which has areplaceable element thus reducing the maintenance cost considerably.

Another object of the invention is to provide a device of the characterherewith described in which the bypass valve prevents dumping" fromoccurring.

A yet further object of the invention is to provide a device of thecharacter herewith described in which the filtering element is enclosedwithin an outer and inner casing thus preventing collapse of thefiltering media due to oil pressure, sludge and the like.

A yet further object of the invention is to provide a device of thecharacter herewith described which is simple in construction, economicalin manufacture, and otherwise well suited to the purpose for which it isdesigned.

With the foregoing in view, and such other or further purposes,advantages or novel features as may become apparent from considerationof this disclosure and specification, the present invention consists of,and is hereby claimed to reside in, the inventive concept which iscomprised, embodied, embraced, or included in the method, process,construction, composition, arrangement or combination of parts, or newuse of any of the foregoing, of which concept, one or more specificembodiments of same are herein exemplified as illustrative only of suchconcept, reference being had to the accompanying Figures in which:

FIG. 1 is a sectional exploded view of my filter assembly.

FIG. 2 is a fragmentary view of the lower end of the filter elementshowing the bypass valve.

FIG. 3 is a top plan view of the base cap per se.

FIG. 4 is a horizontal sectional view of the filter element per se.

In the drawings, like characters of reference indicate correspondingparts in the difierent Figures.

Proceeding therefore to describe the invention in detail, I have foundit preferable to form the filter assembly from diecast aluminum or thelike although it will be understood, of course, other materials may beused.

Reference character illustrates a substantially cylindrical outer casinghaving domed upper end 11 closing off the casing and terminating in ahexagonal nut 12 formed integrally upon the domed upper end 11 andconcentrically therewith.

Also formed integrally with the casing is a concentrically locatedhollow spindle 13 also closed at the upper end 14 thereof and open atthe base 15 as is the casing at the base 16.

This spindle is provided with oil apertures 17 through the walls thereofto the interior bore 18, said apertures being situated intermediate theends of the spindle but towards the upper end 14 thereof.

The lower end 19 of the spindle is internally screw threaded as at 20 toengage over the conventional oil conduit (not illustrated), normallypresent on automotive engines.

This conduit feeds oil from the filter to the engine bearings in theusual way.

A base cap collectively designated 21 is provided detachably engageableover the lower open end 16 of the easing 10, said base cap having acentrally located aperture 22 engageable over the oil conduit whichcommunicates with the lower end 19 of the spindle as hereinbeforedescribed.

A resilient sealing washer 23 is seated around the underside 24 of thecap and engages the area around the oil conduit thus sealing the oilconduit efi'ectively.

Situated outboard of the central aperture 22 is a plurality of oilintake apertures 25 through which oil is pumped from the engine pump toan area surrounding the oil conduit. This construction is conventionaland therefore has not been illustrated.

An annular channel 26 is formed just inboard of the perimeter 27 of thecap upon the upper side 28 thereof and a resilient sealing washer 29 isseated within this channel. The lower end 30 of the end wall of thecasing 10 seats within this channel upon the sealing washer thusassisting in the location of the cap upon the casing and also giving anefiective seal around this area. Due to the cap engaging over the end30, any increase in oil pressure increases the sealing capacity of theseal rather than weakening same as happens in conventional seals.

An annular bead 31 is formed also on the upper surface 28 of the capjust outboard of the oil intake apertures 25 and a nonreturn valve inthe form of a plain resilient washer 32 seats upon this headapproximately in the position shown in FIG. 1.

The internal bore of this washer is slightly smaller than the bead 31 sothat the washer has to be stretched slightly to engage the bead. Thiscauses the outer portion of the washer to act as a nonreturn valve. Thisaction is shown in dotted line in FIG. 1.

Reference should next be made to FIGS. 1 and 4 in which referencecharacter 33 illustrates generally the filter element. This consists ofa perforated outer cylindrical casing 34 and a perforated inner casing35, the inner casing being formed substantially star-shaped when viewedin plan as shown in FIG. 4. This increases the effectiveness of thecontact area of the filter media 36 situated between the outer and innercasing 34 and 35. This filtering media can be any well known materialbut is preferably a very porous, nonwoven rayon material in a pluralityof layers wound around the inner casing which is then in serted withinthe outer casing. The upper and lower ends of this casing are sealed byend caps 37 and 38 respectively, said end caps being centrally aperturedas at 39 to engage over the aforementioned spindle 13 when the device isassembled.

A rubber washer 40 is secured to the underside of the upper cap 37 by ametal cap 40' and surrounds the spindle thus sealing same. It will benoted that the spindle tapers inasmuch as the diameter of the lower end15 is less than the upper end thus leaving an annular space 41 adjacentthe lower end between the spindle and the wall of the cap 38. A bypassnonreturn valve 42 is provided and comprises a planar resilient washerheld in place with a metal cap 40 upon the inner surface 43 of the lowercap 38 surrounding the aperture 39 and overlapping as clearly shown inFIG. 2. This washer embraces the lower end 15 of the spindle andnormally prevents oil from passing thereby.

Referring back to FIG. 1, the nonreturn valve 32 is situated between thebase 38 of the filter element and the annular ring 31 on the cap 21. Oilentering apertures 25 deflects this valve or washer away from the base38 thus enabling oil to pass to the annular channel 44 between thefilter element and the easing wall 10. Oil flows upwardly around thefilter element, through the apertures or perforations within the outercasing 34 of the element, through the filtering media 36 and thencethrough the inner canister 35 of the filtering media to the area 41surrounding the spindle 13. It then flows through the oil apertures 17to the interior 18 of the spindle and thence downwardly to the oilconduit (not illustrated).

When the filter media is clogged or the oil is cold and thus relativelythick, the space provided by the nonreturn valve 32 is not sufficientfor the oil to pass through and therefore in order to avoid starving theengine bearings of oil the aforementioned bypass valve 42 is provided.As soon as the pressure builds to a predetermined figure, theoverlapping portion of this washer deflects upwardly as shown in phantomby reference character 42 in H6. 2 thus enabling oil to pass directly tothe annular space 41 and thence through the oil aperture 17 to theinterior of the spindle 18.

The principle advantage of this construction is that any dirt notentrapped within the filter media, rests in the annular recess 44 formedin the upper surface of the cap 28 and between the stiffening ribs 45 asshown in FIG. 3, and this dirt is not washed by the bypassing oil as itis is in conventional spin-on-type filters.

Another advantage is the fact that this construction of nonretum valvecannot jam in the open position. Conventional valves often jam open thuscausing oil to bypass the filter indefinitely thus negating anyadvantages the filter may offer.

To replace the filter element it is merely necessary to engage a wrenchover the hexagonal nut portion 12, remove the filter assembly from theoil conduit, withdraw the element 33 and replace it with a new one andthen replace the entire assembly on the oil conduit, an operation thattakes only a few minutes and is therefore economical to perform.

Reference should be made to the star-shaped inner casing 35 of theelement. This configuration gives a considerable increase in oil escapearea. Conventionally the inner bore is just a relatively small cylinderso that the ratio of the area of the outer casing to the inner casing isrelatively large. This may cause considerable back pressure particularlyif the filter contains any amount of sludge.

Referring back to the nonreturn valve in the form of washer 32, this isof particular use when the filter is lying horizontally.

However, when the filter is situated at an angle or vertically, it isnot necessary to utilize the nonretum valve washer 32. Reference shouldbe made to FIG. 1 in which it will be seen that the depth of the filterelement is slightly less than the depth of the casing so that the filterelement is capable of slight upward and downward movement relative tothe case.

When in the vertical or diagonal position, the weight of the filterelement will ensure that the base of the element registers upon theannular bead 31 thus sealing off effectively until pressure of oil liftsthe filter element upwardly slightly and permits oil to pass thereby.

When the filter is assembled of course, the screw threading engagementof the filter assembly with the engine block clamps the bottom lidassembly 21 firmly to the casing 10. However, in placing or whenoffering up the filter element for assembly to the engine, it isnecessary to hold the lid on frictionally and l have provided aplurality of friction holding pads 46 around the outer lower perimeterof the casing 10 frictionally engageable by a plurality of similarholding pads 47 situated on the wall of the annular groove 26. When theportion 21 is entered over the lower side of the casing, a slightrotation will cause the pads 46 and 47 to come into interference thusgiving frictional holding while the filter assembly is being ofiered tothe engine block.

As mentioned above, the construction of the filter portion of the unitis made with a multilayered, very porous nonwoven rayon cloth. Since thepores in the various layers of cloth do not fall in line with oneanother, they cause a diversion in the flow of the oil as it passesthrough the layers. This action causes the impurities to becomeentrapped between the layers of cloth.

One very important feature gained by the use of this construction andmaterial is the fact that it provides a simple but accurate method forincreasing or decreasing the density to suit any particular requirement.This is accomplished by adding or reducing the layers of cloth withinthe filter element and is particularly useful where a requirement callsfor removal of the specified micron-sized particles. The aforementionedstar-shaped core 35 not only supplies a large escape area and results ina very free-flowing unit but also acts as a support for the filterelement.

It has been noted that a pleated paper" type filter has a large escapearea. However, tests indicate that the oil pressure pushing on theoutside of the pleat pinches it together at the root diameter, therebygiving it very little more escape area than the tubular metal supportinside the paper filter. The starshaped core 35 prevents this pinchingand supports the element at all times.

Needless to say the outer metal sleeve 34 and the inner starshapedsupport 35 are well provided with governed openings to ensure equal flowdistribution throughout the entire area of the filter. The perforationsof the inner support 35 are so located to prevent any migration offibers.

Various modificatons can be made within the scope of the inventiveconcept which is herein disclosed and/or claimed.

What I claim as my invention is:

l. A spin-on-type filter for oil systems of automotive engines and thelike comprising in combination an outer cylindrical casing open at thebase thereof, a hollow spindle formed integrally with said casing andextending concentrically from the closed end internally to the open end,said spindle being open at the lower end thereof and having oil entranceports through the wall thereof and intermediate the ends thereof, thelower end of said spindle being internally screw threaded to engage overthe conventional oil conduit, a base cap sealably engageable over saidlower end of said cylindrical casing, an oil conduit aperture situatedcentrally of said cap, oil intake apertures in said cap concentricallysurrounding said oil conduit aperture, a replaceable oil filter elementin said casing surrounding said spindle, nonretum valve means betweensaid oil intake apertures and the outer surface of said filter element,and nonreturn bypass valve means surrounding said spindle between saidspindle and the inner bore of said filter element.

2. The device according to claim 1 in which said nonreturn valve meanscomprises a resilient planar gasket surrounding said oil intakeapertures and cooperating between said cap and the base of said filterelement.

3. The device according to claim 2 in which the sealing engagement ofsaid base cap includes'a concentrically situated annular channel formedin said cap adjacent the perimeter thereof, and a resilient washer insaid channel, said lower end of said casing seating in said channel andengaging said washer.

4. The device according to claim 2 in which said bypass nonretum valvemeans comprises a resilient gland secured to said inner bore of saidfilter element at the base thereof and engaging snugly around saidspindle whereby pressure on the underside of the gland moves sameupwardly and away from said spindle.

5. The device according to claim 4 in which the sealing engagement ofsaid base cap includes a concentrically situated annular channel formedin said cap adjacent the perimeter thereof, and a resilient washer insaid channel, said lower end of said casing seating in said channel andengaging said washer.

6. The device according to claim 4 in which said filter element includesan outer perforated canister and an inner perforated canister, upper andlower end caps apertured to engage said spindle, and filtering mediabetween said canisters, said inner perforated canister, when viewed inplan, being substantially star-shaped to increase the contact area ofsaid filter media and escape area of oil flow.

7. The device according to claim 1 in which said bypass nonretum valvemeans comprises a resilient gland secured to said inner bore of saidfilter element at the base thereof and engaging snugly around saidspindle whereby pressure on the underside of said gland moves sameupwardly and away from said spindle.

8. The device according to claim 7 in which the sealing engagement ofsaid base cap includes a concentrically situated annular channel formedin said cap adjacent the perimeter thereof, and a resilient washer insaid channel, said lower end of said casing seating in said channel andengaging said washer.

9. The device according to claim 8 in which said filter element includesan outer perforated canister and an inner perforated canister, upper andlower end caps apertured to engage said spindle, and filtering mediabetween said canisters, said inner perforated canister, when viewed inplan, being substantially star-shaped to increase the contact area ofsaid filter media and escape area of oil flow.

10. The device according to claim 1 in which the sealing engagement ofsaid base cap includes a concentrically situated annular channel formedin said cap adjacent the perimeter thereof, and a resilient washer insaid channel, said lower end

1. A spin-on type filter for oil systems of automotive engines and thelike comprising in combination an outer cylindrical casing open at thebase thereof, a hollow spindle formed integrally with said casing andextending concentrically from the closed end internally to the open end,said spindle being open at the lower end thereof and having oil entranceports through the wall thereof and intermediate the ends thereof, thelower end of said spindle being internally screw threaded to engage overthe conventional oil conduit, a base cap sealably engageable over saidlower end of said cylindrical casing, an oil conduit aperture situatedcentrally of said cap, oil intake apertures in said cap concentricallysurrounding said oil conduit aperture, a replaceable oil filter elementin said casing surrounding said spindle, nonreturn valve means betweensaid oil intake apertures and the outer surface of said filter element,and nonreturn bypass valve means surrounding said spindle between saidspindle and the inner bore of said filter element.
 2. The deviceaccording to claim 1 in which said nonreturn valve means comprises aresilient planar gasket surrounding said oil intake apertures andcooperating between said cap and the base of said filter element.
 3. Thedevice according to claim 2 in which the sealing engagement of said basecap includes a concentrically situated annular channel formed in saidcap adjacent the perimeter thereof, and a resilient washer in saidchannel, said lower end of said casing seating in said channel andengaging said washer.
 4. The device according to claim 2 in which saidbypass nonreturn valve means comprises A resilient gland secured to saidinner bore of said filter element at the base thereof and engagingsnugly around said spindle whereby pressure on the underside of thegland moves same upwardly and away from said spindle.
 5. The deviceaccording to claim 4 in which the sealing engagement of said base capincludes a concentrically situated annular channel formed in said capadjacent the perimeter thereof, and a resilient washer in said channel,said lower end of said casing seating in said channel and engaging saidwasher.
 6. The device according to claim 4 in which said filter elementincludes an outer perforated canister and an inner perforated canister,upper and lower end caps apertured to engage said spindle, and filteringmedia between said canisters, said inner perforated canister, whenviewed in plan, being substantially star-shaped to increase the contactarea of said filter media and escape area of oil flow.
 7. The deviceaccording to claim 1 in which said bypass nonreturn valve meanscomprises a resilient gland secured to said inner bore of said filterelement at the base thereof and engaging snugly around said spindlewhereby pressure on the underside of said gland moves same upwardly andaway from said spindle.
 8. The device according to claim 7 in which thesealing engagement of said base cap includes a concentrically situatedannular channel formed in said cap adjacent the perimeter thereof, and aresilient washer in said channel, said lower end of said casing seatingin said channel and engaging said washer.
 9. The device according toclaim 8 in which said filter element includes an outer perforatedcanister and an inner perforated canister, upper and lower end capsapertured to engage said spindle, and filtering media between saidcanisters, said inner perforated canister, when viewed in plan, beingsubstantially star-shaped to increase the contact area of said filtermedia and escape area of oil flow.
 10. The device according to claim 1in which the sealing engagement of said base cap includes aconcentrically situated annular channel formed in said cap adjacent theperimeter thereof, and a resilient washer in said channel, said lowerend of said casing seating in said channel and engaging said washer. 11.The device according to claim 1 in which said filter element includes anouter perforated canister and an inner perforated canister, upper andlower end caps apertured to engage said spindle, and filtering mediabetween said canisters, said inner perforated canister, when viewed inplan, being substantially star-shaped to increase the contact area ofsaid filter media and escape area of oil flow.